Low noise multistage avalanche photodetector
US4203124A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 6, 1978 |
| Grant date | May 13, 1980 |
| Priority date | — |
| Expiry date | Oct 6, 1998 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F30/2255
Abstract
Devices constructed according to the present invention provide low noise avalanche photodetectors. The devices are comprised of a sequence of at least four layers of semiconductor material of alternating opposed conductivity. In a first embodiment the layers form alternating homojunctions and heterojunctions at the interface between adjacent layers, and the bandgap of the layers on either side of the homojunctions decreases in the direction of the propagating signal. In another embodiment the layers form heterojunctions at the interfaces between adjacent layers; the layers are grouped into a sequence of pairs of layers where the bandgap of the two layers in each pair are substantially equal; and the bandgap of the layers in the sequence of pairs of layers decreases in the direction of the propagating signal. The effect of the structure of the multilayer device is to create traps for one sign of carrier and to prevent the trapped carrier from avalanching through amplification regions of the device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.